Healthy Aging and Longevity
Deep Dive on Longevity Lifestyles
This is one of three articles on healthy aging and longevity. Companion articles include:
It’s treacherous to make broad generalizations about lifestyles and practices that are shared across diverse populations of exceptional agers. It’s difficult to quantify the benefit of activities like diet and exercise through retrospective observational research, and confirmation bias is always a risk. With these caveats, here are findings from some of the most rigorous observational studies out there.
Positive Psychology
Thanks in large part to their extraverted personalities and strong social support, investigators from the Heidelberg Centenarian Study found that, despite their infirmities, those that make it to 100 are happy and content. Centenarians even maintain a sense of wellbeing after their cognitive status begins to decline.
It should come as no surprise that centenarians are generally less depressed than the rest of us (although being institutionalized or suffering cognitive decline muddies this picture). This finding holds true across cohorts from inner-city New York to rural China.
In a magazine interview, Dr. Craig Willcox, a gerontologist and co-principal investigator of the Okinawa Centenarian Study, described Okinawans as “happy-go-lucky,” confident that “it will all work out in the end.”
The most consistent personality trait found in almost every psychological study of centenarians is a low level of neuroticism (as measured by researchers via standardized questionnaires) — meaning that centenarians tend to be calmer, less reactive to stress, and less likely to feel tense or rattled. A large Swedish study characterized centenarians as “dependable, reliable, mature, and conscientious,” as well as “easygoing, …relaxed, …and not prone to anxiety.” No wonder they are better able to cope with their infirmities.
A Japanese study of female centenarians showed them to have high scores for conscientiousness and extraversion compared to less-old elderly subjects. These findings were also reported in a similar study of U.S. centenarians, who also showed higher conscientiousness and lower neuroticism than average (again, measured using standard psychological profiling). Yet another study found they shared favorable personality characteristics, such as positive attitude towards life (optimism, easygoing, laughter) and greater comfort with emotional expression.
Another characteristic commonly associated with the oldest-old is resilience. Based on a massive study of thousands of Chinese centenarians followed for over a decade, investigators discovered that centenarians were “significantly more resilient than any other age group of the elderly population.” In fact, subjects in their mid-nineties that had higher resilience scores in personality tests were over forty percent more likely to reach the one-hundred-year milestone than those that did not. Since centenarians are survivors, it is not terribly surprising that they are resilient and have found effective ways of coping with their infirmities and limitations.
This point about resilience could not be made any clearer than by a study based on the gigantic Chinese Longitudinal Healthy Longevity Survey. The graph below shows various health indicators and subjective wellbeing scores from over 90,000 interviews. Here’s an eye-popping fact that points to the resilience of the oldest old: in their nineties and beyond, despite losing their cognitive function, their ability to take care of themselves, and even their ability to turn around in a full circle, these elders maintained their satisfaction with life and self-reported feelings of good health.
Health Indicators and Subjective Wellbeing Among Elderly Chinese
Here’s one, last psychological factor that distinguishes healthy agers. To me, this one feels like the biggest of all. Centenarians still have purpose — a reason for living. This is best exemplified by Okinawan Blue Zone elders. It turns out that Okinawa is the birthplace of a practice called ikigai (pronounced EYE-kih-guy), which is loosely translates as the happiness of always being busy — something that Okinawans and many other Japanese believe is the secret to a long, healthy life. The elements of ikigai are pictured below. When all these elements are working together in harmony, you have found your ikigai.
According to author Gordon Matthews, ikigai is related to two other Japanese ideas: ittaikan — which reflects “a sense of oneness with, or commitment to, a group or role,” and jiko jitsugen — which is about self-realization.
Investigators who led the original Blue Zones work explain that,
“Older Okinawans can readily articulate the reason they get up in the morning. Their purpose-imbued lives give them clear roles of responsibility and feelings of being needed well into their hundreds.”
In support of the importance of ikigai, a 2016 meta-analysis of prospective studies totaling over 136,000 subjects found that people with a strong sense of purpose in life enjoyed a lower risk of death and cardiovascular events. This tees-up the intriguing hypothesis that ikigai matters, whether you live on a subtropical island archipelago or in suburban Cleveland.
Healthy Diet and Physical Activity
Not surprisingly, few centenarians are obese, and most (but not all) studies suggest that they enjoy metabolic markers and body mass indexes that match people less than half their age. Putting genetic influences aside for now, this suggests that centenarians tend to practice a lifetime of healthy eating and physical activity.
Centenarian dietary practices that have been studied the most are found in two Blue Zones — Okinawa in Japan, and various longevity hotspots in Italy. While studies based on self-reported food diaries are prone to inaccuracies, this is the best we have. In fact, there is not a single study of centenarians or Blue Zones that posits a scientific association between dietary components and more or less longevity among its population. With this caveat in mind, here are some observations which are the subject of endless public debate and experimentation.
Okinawa, Japan. The traditional Okinawan diet includes moderate consumption of fish, high consumption of vegetables and legumes, and low consumption of meat and dairy products, with most protein from soy. Carbohydrates come from whole grains like brown rice. The oft-repeated trope that Okinawans follow a calorie-restricted diet is not true. A dietary survey done after World War II in 1949 did find that they were calorie-deprived, but nothing indicates this persisted much beyond the post-war era.
Sardinia, Italy. The traditional lifestyle involves shepherding livestock from the inner mountains to the plains. According to Dan Buettner, the diet that goes along with this lifestyle includes lots of cheese from goats and sheep; a moderate amount of carbs from flat bread, sourdough, and barley; plenty of local vegetables such as fennel, fava beans, chickpeas, and tomatoes — as well as almonds, milk thistle tea, and wine from Grenache grapes.
Sicily, Italy. Sicilians follow a traditional Mediterranean diet, which includes low glycemic index foods, low consumption of saturated fat and meat, and high consumption of fruits and vegetables. Meals are small, and spread across three eating occasions with no snacking. Red wine is often taken at dinnertime.
Acciaroli, Italy. Diets in this Italian hamlet revolve around locally caught fish, home-reared rabbits and chickens, and lots of vegetables and fruit. They use phytochemical-rich herbs such as rosemary and follow a traditional Mediterranean diet.
Ikaria, Greece. Ikarians also follow a Mediterranean diet, including lots of olive oil, fruits, and vegetables. They eat red meat (mostly goat) once or twice weekly.Like many from this part of Europe, Ikarians drink red wine at dinner. They are mostly Greek Orthodox Christians, a practice that calls for religious fasts throughout the year.
Physical activity is more challenging to study among centenarians, as it depends on their accurate recall of lifelong practices. To get around this, research is typically done on elders in their eighties and nineties. The largest study I could find was, again, the Chinese Longitudinal Healthy Longevity Survey. In 2015, investigators followed a massive cohort of 9,000 elders over eighty years of age for nearly fifteen years. They found that physical activity among the oldest-olds was associated with a 27 percent lower risk of mortality compared with no activity. Also, compared to other practices such as diet, physical activity had the largest effect on median age of death.
These findings agree with anecdotal observations from Blue Zone investigators which have been publicized by the media over the years — elderly Sardinian men slinging pigs around one-handed, a 104-year-old Okinawan who still enjoys gardening, and a 91-year-old Seventh-Day Adventist in Loma Linda who is still a practicing surgeon. Lifelong movement and physical activity matter, perhaps even more than structured exercise.
Communal Social Beliefs, Norms, and Behaviors
Even more than lifestyle factors, it is nearly impossible to generalize a set of social beliefs, norms, and behaviors that are common across diverse longevity hotspots and study cohorts. Looking at small, geographically- and culturally-isolated Blue Zone villages simplifies this challenge. Not surprisingly, healthy Blue Zone elders tend to be quite religious and accustomed to periodic day-long religious fasts. They are hardworking, and exist in tightknit social networks typical of isolated rural communities.
A large study looking at the association between religiosity and longevity involved over 9,000 elderly Chinese who were followed for three years. During this period, frequent religious participants were 21 percent less likely to die than non-participants. While cause and effect cannot be determined, these subjects were probably sustained by the social support and sense of purpose gained from participating in an organized religion.
Blue Zone elders enjoy strong social networks outside of organized religion, too. The Okinawan Research Center explains that their elders often form social safety nets called a moai (pronounced mo-AHY), informal groups of people who meet regularly, share common interests, and support each other. Whenever a member falls on hard times, their moai provides financial and emotional support. Deep social support is observed in other Blue Zone villages, too. For instance, as reported by journalist Richard Eisenberg, in the Blue Zones of Costa Rica, Greece, and Sardinia, children of centenarians frequently provide unpaid caregiving.
Takeaways
This article reviewed observation evidence that certain practices and lifestyles are associated with exceptional health and longevity. These include the following.
Culture and geography. The mechanisms of extreme long life are challenging to untangle, but culture and geography likely play important roles. For instance, low-stress lifestyles, a cultural bias toward working into old age, which are often observed in isolated longevity hotspots around the world.
Positive psychology. Purposeful living, a less reactive personality, and psychological resilience are all associated with an extended, healthy lifespan. So are conscientiousness, positive outlook, and comfort with expressing emotions.
Healthy diet and physical activity. Following a typically Mediterranean plant-rich diet with meat a couple times per week, eating in moderation, and regular physical activity are often associated with healthy aging.
Communal social beliefs, norms, and behaviors. Living in caring communities united by shared values and close family ties are both characteristic of people who live into extreme old age.
To learn more, click over to my companion articles, Genetics and Lifestyle: What Our Healthy Elders Teach Us and Longevity Genes and Phenotypes.
